Internal combustion engine



June 25, 1940. c, SHIRLEY 2,205,675

INTERNAL COMBUSTION ENGINE Filed April 28, 1938 3 Sheets-Sheet l s I I I I. I

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INVENTOR A TTORNE Y June 25, 1940. Y J. c. SHIRLEY 2,205,675

INTERNAL COMBUSTION ENGINE Filed April 28, 1938 3 Sheets-Shget 2 m INVENTOR James C. Shir/e5 Fig-4'. 4 BY A TTORNE Y June 25, 1940. J. c. SHIRLEY INTERNAL COMBUSTION ENGINE Filed April 28, 1938 3 Sheets-Sheet 3 Fig.5.

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INVENTOR James C. Shi 9 ,1 TTOR'NE Y Patented June 25, 1940 sra'rss INTERNAL COMBUSTION ENGINE James 0. Shirley, Chattanooga, Tenn. Application April 28, 1938, Serial No. 204,767

7 Claims.

My invention relates to engines and more particularly to internal combustionengines of the plural piston type.

Inthe prior art, of internal combustion engines, it has been the practice to employ cylinders that carry a single piston which reciprocates therein. The upper end of the cylinder is ordinarily closed by the engine head and the combustion chamber is located between the pis- 10 ton and the head. Ports are provided at various places for leading the mixture into the chamber and for removing the gases of a combustion. Since the single piston is the only part which moves in response to the combustion of the gases in the chamber, Whatever expansion of the gas takes place must be taken care of by movement of the single piston. In this way, a considerable amount of heat is lost in the head and expansion of the gas is accordingly limited, thereby dissipating the energy and losing it. In such a construction, the force imparted to the crank shaft is always in the same direction, that mm the direction away from the piston. This places great strain upon the bearings and creates an unbalanced condition.

While it is true that some effort has beenmade in such patents as Craig, 644,004; Steinbecker 1,- 066,672; Ramesh 1,166,714; and Chattain 1,112,- 263 and others to provide a double piston engine.

However, in most of these constructions, the upper end of the cylinder is slotted to receive a cross arm carried by the upper piston and secured oneither side by connecting rods to the crank shaft. The slotting of the cylinder walls 5 tends to weaken them,,permits increased loss of gases around the piston and allows the lubricant for the pistons to escape therethrough. As the cross arm reciprocates in the slotted guides or walls of the piston, Wear takes place and looseness'develops causing. the upper piston to be thrust, against some parts of the cylinder Wall more than against others, thereby causing uneven wearing of the parts of the cylinder. Furthermore, such structures as Craig, supra, and

Ramesh, supra, employ valve chambers in connection with cylinders. This provides a considerable space to which the gases can flow expand and produce no work and in these structures, the inlet valve depends for its operation upon suction created by movement of the pistons to overcome the seating force of the springs upon those valves.

There is no positive means provided for their operation. If their spring tension is too great,

then theywill not open sufliciently to-permit the inflow of the proper amount of air and fuel. The use of a portion of one of the pistons asan air compressor in the above structure produces an uneven balance, since one piston is of greater weight than the other." Further, itsis almost impossible to assemble such a piston in the cylinder due to the necessity for contracting the rings when assembling,

Applicant with aknowledge of all these 010- jectionsto and defectsin the prior art has for an object of his invention the provision. of an internal combustion engine having a plurality of pistons for each cylinder which pistons are joined through connecting rods to crankshafts adjacent the extremities of the cylinder, the

crank shafts being connected to a drive shaft through connecting arms or rods to produce a balanced efiect upon the drive shaft andp'ermit the use of unslotted cylinders free from the effects of uneven wear and other disadvantages, introduced by the use of a cross head with the piston. Applicant has as another object of his invention the provision of a plural piston engine hav ing a single combustion chamberxwith valves communicating with said chamber to lead air and fuel into the chamber for combustion, or for removing the products of combustionfromthe chamber and cam means for engaging and controlling said valves to properly operate them in 30 carrying out these functions.

Applicant has as a further object of his inven tion the provision of a plural piston engine which is more efllcient than the, single piston engine, and which will permit the gases ,of combustion to expand further and which will dissipate less of the heat of combustion. Applicant has as a'further object of his invention the provision of an enginehaving a series of piston housings, all communicating with a common combustion chamber, thereby eliminating the valves, valve operating equipment and reducsection, of one form of my' improved engine. Fig 55 ure 2 is a side elevation of the same form of engine. Figure 3 is a side elevation of another form of my improved engine. Figure 4 is a detail of the improved valve, in section, used in connection with my invention. Figure 5 is a planed view of the engine of Figure 3. Figure 6 is a detail elevation of the cam for operating the valves in the first form of applicants invention. Figure '7 is a fragmental sectional view of the cam of Figure 6.

Referring to the drawings in detail, 2 designates a cylinder casing having annular chambers in the walls thereof for the reception of water or other cooling medium. On one side of the cylinder casing 2 is a base 23 for mounting the engine on the floor or otherwise. Disposed within the cylinder bore in face to face relation are pistons I, I encircled by the usual piston rings. At either end of the casing 2 are caps 6, 6 which seal the casing and define chambers in which are mounted crank shafts II, II that set in appropriate bearings in the walls of casing 2. The caps 6, 6 are rigidly secured to the casing 2 by any appropriate means. Joining the cranks 5, 5 of the crank shafts II, II to the pistons I, I are connecting rods 3, 3. The ends of these connecting rods 3, 3 are pivotally joined to the pistons I, I by pins 4, 4 of the usual type.

Projecting from one end of the crank shafts II, II, after it passesthrough the casing 2, are cranks 9, 9 which are joined through connecting rods In, It] to drive shaft I9 which is mounted in bearings intermediate the casing 2. These bearings are carried by base 23 and casing 2. Mounted on a drive shaft I9 and rotatable therewith, is a pinion 20. Meshed with the pinion 20 and driven thereby is a gear H which is mounted adjacent one end of shaft 22, and is ordinarily twice the diameter of the pinion. The shaft 22 is carried by appropriate bearings mounted or otherwise secured to the casing 2. Mounted on the opposite end of shaft 22 is cam I2 having an outer raised portion I3 and an inner raised portion I4 to engage the valve stems I5 and 24, respectively, thereby depressing said stems and operating the corresponding valves.

A combustion chamber 42 is defined by the faces of pistons I, I and the walls of casing 2. Mounted in the walls of easing 2 and communicating with combustion chamber 42 are valves 25, 43, the former of which feeds air and fuel to the combustion chamber 42 through port 44 while the latter removes exhaust gases through port 26. The valve 25 has a stem 24, extending through the walls of housing I6 and is provided with a recess 45 in which is mounted a coiled spring 41 about the stem 24, having one end resting against packing element 28 and the other against retainer 48 which in turn abuts against stop 3I. The structure of the exhaust valve 43 is very similar, I5 rep-resents the stem, 46 the recess, 29 the spring, 49 the packing element, 30 the retainer and 50 the stop. Both stems 24, I5 project beyond the walls of housing It and are adapted to engage raised surfaces on cam I2. While this type of valve is used, ,it is contemplated that other forms of valves which perform the same function in the same way may be substituted therefor.

In the position shown by Figure 1, the pistons I, I are in the position immediately after ignition which raises the ignitedjgases to a-high temperature causing them to exert a great force on the pistons I, I moving them apart. As they move apart, crank shafts II, II are rotated in a counter-clockwise direction revolving drive shaft I9 in the same direction with them. The pinion 20 then rotates gear I! and cam I2 on shaft 22 in a clockwise direction causing raised portion I4 of the cam to be brought into contact with stem I5 of valve 43 as the pistons I, I near the outer extremity of their stroke just as the gas reaches its maximum expansion. As cam I2 continues to rotate, stem 24 is depressed inwardly by engagement with the raised portion, l3 of the cam. The pistons travel back towards each other as the raised portion I4 of the cam I2 depresses the stem I5 and maintains it in depressed position, thus unseating valve 43 and permitting the gases of combustion to escape from the cylinder 2 through port 26.

As the pistons I, I again reach the inner extremity of their stroke, the cam I2 has rotated to a point where the raised portion I4 has cleared the stem I5, permitting the valve 43 to again seat and closing the port 26 from the cylinder 2.

The pistons I, I again move apart and the rotation of the main drive shaft I9 in a counterclockwise direction continues to rotate the cam I2 in a clockwise direction moving the raised portion I3 towards the valve stem 24 as the pistons move apart. As the cam I2 continues to rotate, raised portion I3 engages stem 24 depressing it and opening the valve 25. This permits air and fuel to flow from port 44 into the combustion chamber 42.

When pistons I, I again reach their outer extremity', raised portion I3 of cam I2 moves out of engagement with the valve stem 24 permits spring 41 to act upon it, and closes port 44 from the combustion chamber 42, thereby preventing further flow of fuel and air to the cylinder. As the pistons move back towards each other, they compress the air and gases causing them to reach a high temperature and either igniting them by reason of such temperature or raising their temperature to such a point that ignition easily takes place by some appropriate supplemental means, (such as a spark plug) or other device.

For convenience and clarity in the drawings, the lubrication system has not been disclosed, but any form of lubrication system of the well known types may be used. Likewise the flywheel and other supplemental structure have been omitted since they do not contribute to the invention in any way and may be associated with this structure in any well known manner. While only a single cylinder is shown in Figures 1 and 2, it will be obvious that a number of cylinders may be associated together in the completed invention Without departing from the scope of this invention.

Referring to the modification of Figures 3 and 5 the cylinder casing 2 has four arms although more or less arms may be employed if desired. These arms radiate from a central portion which forms a combustion chamber. Disposed within each arm is a piston I. Mounted in each outer extremity of each arm is a crank shaft I I' having cranks 5' which are joined to pistons I through connecting rods 3" by means of the usual piston pins 4. Extending from the arms of one side of the forward cylinder upon extensions of crank shafts II are cranks 33, 3E, 33, 36'. A diagonally opposite upper and lower crank project out beyond the others on extensions 44'. The diagonally opposite upper and lower cranks 33', 33, and 36', 35 are connected to'crank M and 40' respectively, of a drive shaft I9, by connecting rods 32, 32' and 35" 35 respectively.

Extending from the rear of the forward cylinder are extensions 43 of crank shafts II. These extensions are joined integrally or otherwise to the crank shafts II of the back cylinder as shown in Figure 5.

On the rear of the forward cylinder and on the front of the back cylinder, positioned intermediate the arms and communicating with the combustion chambers are valve housings I5 of the type disclosed on Figure 4. Intermediate the valve housing, 26, I6 projects a portion of the cam I2 which is mounted on control shaft 42- carried in appropriate bearings by the cylinders. The shaft 42 is actuated by gear ll driven by pinion 2!! on the'drive shaft Is.

The cam I2 differs from that of Figures 6 and 7 only by having raised portions on both faces to operate the valves'of two cylinders instead of one.

The cylinders are mounted upon and supported by an appropriate base 23'. The drive shaft I9 is mounted in the forward cylinder and on a bearing 45. The caps 6 are of similar construction to that disclosed in the first modification.

The operation of this modification is somewhat similar to that of the first modification.

Referring to Figures 3 and 5, combustion has just taken place in the combustion chamber of the forward cylinder, which chamber is located at the junction of the arms. The gases expand due to the heat of combustion, exerting force upon the pistons causing them to move outwardly to permit such expansion, thus turning the crank shafts II and the drive shaft I9 in a clockw se direction. Rotation of the drive shaft I9 in a clockwise direction drives the control shaft 42 in a counter-clockwise direction, causing the cam I2 to depress the valve I5 of the back cylinder so that air and fuel are sucked or otherwise led into the cylinder as the pistons move about, due to the rotation of the crank shafts II.

As the pistons I of the front cylinder reach the outer extremity of their stroke, the cam I2 has rotated to such a position that it depresses valve 24' of that cylinder so that the gases of combustion may be removed as the pistons I begin their inward movement. When the pistons I of the back cylinder reach this position, the cam I2 is then disengaged from the valve stem I5 of the back cylinder, permitting the spring to close the valve and prevent communication with the fuel port 26 as the pistons I take their inward stroke compressing the gas and raising it to a high temperature.

When the pistons I of the forward cylinder reach their inner extremity, the exhaust gases have been forced out through valve 25' and port 44 and the cam I2 has rotated to a point to disengage the valve stem 24' permitting spring 41 to close the exhaust valve 25. At this point, pistons I of the back cylinder havev compressed the fuel and air in the combustion chamber to a high temperature either reaching the ignition point or raising the mixture to such a temperature that it is easily ignited by a supplemental igniter, such as a spark plug (not shown) or other appropriate means.

After ignition takes place in the back cylinder the pistons I are forced apart by the expanding gases. This continues to rotate crank shaft II causing cam I2 to move to the point where it engages and depresses valve stem I5 of the front cylinder. Pistons I of the front cylinder in their movement apart suck or otherwise lead in fuel and air from the port 44 through the open valve 25'. The valve 25 remains open during the most of the downward stroke of the pistons I of the front cylinder.

After the pistons I of the back cylinder reach the extremity of their outward stroke, cam I2 has rotated to such a position as to engage stem 24 of the valve of the back cylinder and depress it, so that pistons I will force the gases of combustion out through port 44 on their inward stroke. At this same time cam I2 has released stem I5 of the valve 43 on the front cylinder cutting off the fuel port 26 from communication with the front cylinder. The continued inward movement of the pistons I of the forward cylinder compresses theair and gases and raises them to a high temperature so that combustion may again take place.

Upon reaching the inner position, the cycle is completed, the valve stem 24 of the back cylinder released and the front cylinder prepared for ignition in its combustion chamber. This operation is continued over and over again. It will be obvious that a fly wheel lubricating system, spark plugs and other supplemental equipment have been omitted from the drawings for the sake of clarity and simplicity since there is nothing novel in its features.

Having thus described my invention, I claim:

1. An engine of the character described comprising a cylinder, a plurality of pistons disposed within said cylinder, a combustion chamber between said pistons, feed and exhaust-ports communicating with the combustion chamber valves for controlling said ports, crank shafts mounted adjacent the ends of the pistons, a drive shaft, means for connecting said crank shafts with said drive shaft, and means actuated by said drive shaft for controlling the operation of said valves.

2. An engine of the character described comprising a cylinder, a plurality of pistons disposed within said cylinder, a combustion chamber between said pistons, feed and exhaust ports communicating with the combustion chamber valves for controlling said ports, crankshafts mounted adjacent the ends of the pistons, a drive shaft, means for connecting said crank shafts with said drive shaft, and means on said drive shaft for operating said valves.

3. An engine of the character described comprising a cylinder, a plurality of pistons disposed within said cylinder, a combustion chamber between said pistons, feed and exhaust ports communicating with the combustion chamber valves for controlling said ports, crank shafts mounted adjacent the ends of the pistons, a. drive shaft, means for connecting said crank shafts with said drive shaft, a control shaft driven by said drive shaft, and a cam on said control shaft for encontrol shaft for engaging said valves to operate them.

5. An engine of the character described comprising a cylinder having a plurality of radial arms, pistons disposed within said arms, a combustion chamber common to said arms, feed and exhaust ports communicating with said chamber, valves for controlling said ports, crank shafts mounted adjacent the ends of said arms, means for connecting the pistons to their respective crank shafts, a drive shaft, means for connecting said crank shafts to said drive shaft, and means driven by said drive shaft for operating said valves.

6. An engine of the character described comprising a cylinder having a plurality of radial arms, pistons disposed within said arms, a combustion chamber common to said arms, ports communicating with said combustion chamber, valves for controlling said ports, crank shafts mounted adjacent the ends of the arms, means for connecting the pistons with their respective crank shafts, a drive shaft, means for joining said drive shaft to said crank shafts, a control shaft driven by said drive shaft, and means on said control shaft for operating said valves.

'7. An engine of the character described comprising a cylinder having a plurality of radial arms, pistons disposed within said arms, a combustion chamber common to said arms, ports communicating with said combustion chamber, valves for controlling said ports, crank shafts mounted adjacent the ends of the arms, means for connecting the pistons with their respective crank shafts, a drive shaft, means for join- 1 ing said drive shaft to said crank shafts, a control shaft driven by said drive shaft, and means on said control shaft for operating said valves.

JAMES C. SHIRLEY. 

